How to implement weapon movement around the player using mouse pos?

I need help with implementation weapon movement around the player with constant radius position. Current image describe how it should work:
Thank you

 

u need parent weapon to empty gameobject, and rotate empty gameobject

Code (CSharp):

1.  void Update() {
2.      Vector3 dir = Input.mousePosition - Camera.main.WorldToScreenPoint(transform.position);
3.      float angle = Mathf.Atan2(dir.y, dir.x) * Mathf.Rad2Deg;
4.      transform.rotation = Quaternion.AngleAxis(angle, Vector3.forward);
5. }

 

Thank you for reply. This code rotates itself weaponObject around but I need to rotate weaponObject around player based on mouse position.

 

as i say before - make weapon parent of emptyobj, and rotate this obj.